DE`SCRIPTION (provided by applicant): This revised proposal is a request for a Zeiss Axioplan 2 imaging system. This microscope has complete differential interference contrast (DIG) and phase optics, dark field and bright field illumination, and multichannel fluorescence. The imaging system includes a high-resolution CCD camera, and deconvolution software to remove out-of focus fluorescence from tissue sections or cultured chamber slide samples. Deconvolution in combination with the high-quality wide-field optics has been shown to provide images of greater resolution than confocal microscopes, and additionally can generate high resolution images of samples with high signal to noise ratios. Deconvolution microscopy also avoids the problems of photobleaching and phototoxicity inherent in scanning confocal microscopy. This microscope system encompasses a broad range of capabilities and its simplicity of use makes it extremely useful in everyday applications. The microscope will serve the needs of a diverse group of investigators from the Tupper Research Institute at Tufts-New England Medical Center. The broad research interests of the core user group includes the study of bacterial and protozoan pathogens, the role of transcriptional regulators in heart development, differentiation of gastrointestinal and pancreatic endocrine cells, focal adhesions in pulmonary vascular endothelial cells, the role of serotonin in vascular remodeling and pulmonary hypotension, hypoxia activation of signal transduction pathways, and the development of acute pancreatitis. The microscope will be incorporated into the Cell and Tissue Analysis Core facility of the Center for Gastroenterology Research on Absorptive and Secretory processes (GRASP) at the Tufts-New England Medical Center where it will be available to both researchers in the core user group and the broader Tufts-NEMC research community.